I actually read the manual and, however, it doesn't say much more that what you wrote.
Let's say my library contains a function foo(). Does that mean that once my library has been loaded, I will be able to use the fucntion?
Also, the library is in C++, does that mean that I will be able to create some instance of classes and use them?
Such information is not part of the manual, and I have not been able to find it anywhere else. As I said, I am quite new to PHP and maybe don't look at the good place.
I'm just seeking some guidance.